This competing continuation application seeks to extend the T32 DK07726 for an additional 5 years of funding and to increase the number of trainees from 4 to 5. This program, Research Training in Pediatric Nephrology, has provided the foundation for our training program for academic investigators in the area of 'pediatric nephrology. The goal of the Children's Hospital Boston Division of Nephrology's fellowship and research training programs is to develop academic physicians and scientists who will establish independent investigative careers in areas relevant to the understanding of childhood kidney diseases. Over the initial funding cycle from AY85-AY89, we firmly established our training program with both clinical and research faculty. Over the second funding cycle from AY90-AY94, we were able to accommodate a full complement of Pediatric Nephrology fellows at every level. During the third funding cycle from AY95-AY99 we expanded the program by adding biomedical scientists to our research faculty and we began to train post- doctoral research fellows. Over the most recent funding cycle from AY00-AY04, we have expanded beyond the level of a divisional training program for Pediatric Nephrologists and we are now training many post- doctoral research fellows interested in the basic science of renal disease. Thus, over the past 10 years, 70 trainees entered our program, 24 are still in training and 46 have completed training. Nearly all of these 46 currently hold full-time academic positions and 22 are currently funded investigators in diverse areas of research all relevant to pediatric nephrology. Furthermore, the trainees completing our program in the past 5 years received 72 awards, 29 grants and contributed to 286 publications. In addition, the research program of full-time division staff has also expanded significantly over the past 5 years, including an expansion of renal developmental biology, glomerular disease, vascular biology, transplantation, and immunology research efforts. Several of our trainees have joined the faculty and have developed complimentary research efforts in stem cell biology, receptor signaling pathways, and bioinformatics. Our research laboratories have undergone substantial expansion and will encompass over 7,000 square feet of space by 2004. We have established close research and training collaborations with laboratories at the Harvard Medical School, Brigham & Women's Hospital, Beth Israel Deaconess Medical Center, Harvard School of Public Health and the Massachusetts Institute of Technology. Thus, trainees who enter our program have exposure to a wide variety of individuals all dedicated to investigative nephrology and have opportunities for rigorous scientific training.